In the event of fire it is important to be able to shut off the flow of oil or gas for example from a well and the object of the passive protection is to minimise heat rise in a control valve and its actuator to enable this to be done. Erosive flames resulting for example from ruptured pipe work in which oil or gas is flowing at pressure, are particularly difficult to protect against with conventional materials.
However as will be appreciated the invention may find uses in other applications and other industries.